結果
問題 | No.2438 Double Least Square |
ユーザー | abap34 |
提出日時 | 2023-08-13 02:04:38 |
言語 | Julia (1.10.2) |
結果 |
AC
|
実行時間 | 1,867 ms / 2,000 ms |
コード長 | 2,591 bytes |
コンパイル時間 | 158 ms |
コンパイル使用メモリ | 6,944 KB |
実行使用メモリ | 341,500 KB |
最終ジャッジ日時 | 2024-04-09 14:30:48 |
合計ジャッジ時間 | 61,168 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
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テストケース
テストケース表示入力 | 結果 | 実行時間 実行使用メモリ |
---|---|---|
testcase_00 | AC | 1,597 ms
310,568 KB |
testcase_01 | AC | 1,600 ms
312,176 KB |
testcase_02 | AC | 1,601 ms
310,844 KB |
testcase_03 | AC | 1,613 ms
310,908 KB |
testcase_04 | AC | 1,604 ms
308,564 KB |
testcase_05 | AC | 1,601 ms
308,920 KB |
testcase_06 | AC | 1,590 ms
312,548 KB |
testcase_07 | AC | 1,604 ms
312,644 KB |
testcase_08 | AC | 1,607 ms
308,692 KB |
testcase_09 | AC | 1,600 ms
310,316 KB |
testcase_10 | AC | 1,849 ms
337,692 KB |
testcase_11 | AC | 1,856 ms
335,672 KB |
testcase_12 | AC | 1,865 ms
337,436 KB |
testcase_13 | AC | 1,837 ms
338,204 KB |
testcase_14 | AC | 1,843 ms
339,672 KB |
testcase_15 | AC | 1,856 ms
337,904 KB |
testcase_16 | AC | 1,864 ms
337,140 KB |
testcase_17 | AC | 1,861 ms
338,020 KB |
testcase_18 | AC | 1,867 ms
336,208 KB |
testcase_19 | AC | 1,866 ms
337,484 KB |
testcase_20 | AC | 1,846 ms
338,792 KB |
testcase_21 | AC | 1,826 ms
338,848 KB |
testcase_22 | AC | 1,813 ms
338,236 KB |
testcase_23 | AC | 1,854 ms
336,696 KB |
testcase_24 | AC | 1,847 ms
339,768 KB |
testcase_25 | AC | 1,831 ms
338,320 KB |
testcase_26 | AC | 1,843 ms
341,500 KB |
testcase_27 | AC | 1,834 ms
337,304 KB |
testcase_28 | AC | 1,844 ms
337,512 KB |
testcase_29 | AC | 1,836 ms
337,608 KB |
testcase_30 | AC | 1,593 ms
310,388 KB |
testcase_31 | AC | 1,594 ms
312,588 KB |
testcase_32 | AC | 1,616 ms
310,608 KB |
ソースコード
using Printf function score(xy, x², y²) if x² == 0 return 0 end coef = xy / x² return y² + (coef^2 * x²) - (2coef * xy) end function main() N = parse(Int, readline()) H = parse(Int, readline()) x = zeros(Int, N) y = zeros(Int, N) for i in 1:N x[i], y[i] = parse.(Int, split(readline())) end INF = 10^16 slopes = zeros(Rational{Int}, N) for i in eachindex(x) if x[i] == 0 slopes[i] = INF else slopes[i] = (y[i] - (H // 2)) // x[i] end end slopes_perm = sortperm(slopes, rev=true) x_perm = sortperm(x, rev=true) # 全部lower xy = sum(x .* y) x² = sum(x .* x) y² = sum(y .* y) L_best = score(xy, x², y²) for i in eachindex(x) upper = slopes_perm[begin:i] lower = slopes_perm[i+1:end] upper_set = Set(upper) upper_x = getindex.(Ref(x), upper) upper_y = getindex.(Ref(y .- H), upper) upper_xy = sum(upper_x .* upper_y) upper_x² = sum(upper_x .* upper_x) upper_y² = sum(upper_y .* upper_y) lower_x = getindex.(Ref(x), lower) lower_y = getindex.(Ref(y), lower) lower_xy = sum(lower_x .* lower_y) lower_x² = sum(lower_x .* lower_x) lower_y² = sum(lower_y .* lower_y) L_u = score(upper_xy, upper_x², upper_y²) L_b = score(lower_xy, lower_x², lower_y²) L = L_u + L_b if L < L_best L_best = L end for j in eachindex(x) new_idx = x_perm[j] if new_idx in upper_set upper_xy -= x[new_idx] * (y[new_idx] - H) upper_x² -= x[new_idx]^2 upper_y² -= (y[new_idx] - H)^2 lower_xy += x[new_idx] * y[new_idx] lower_x² += x[new_idx]^2 lower_y² += y[new_idx]^2 else upper_xy += x[new_idx] * (y[new_idx] - H) upper_x² += x[new_idx]^2 upper_y² += (y[new_idx] - H)^2 lower_xy -= x[new_idx] * y[new_idx] lower_x² -= x[new_idx]^2 lower_y² -= y[new_idx]^2 end L_u = score(upper_xy, upper_x², upper_y²) L_b = score(lower_xy, lower_x², lower_y²) L = L_u + L_b if L < L_best L_best = L end end end @printf "%0.20f\n" L_best end main()